#pragma once
#include "net.hpp"
#include "message.hpp"

namespace RPC
{
   
    class Callback
    {
    public:
        using ptr = std::shared_ptr<Callback>;

        virtual void onMessage(const BaseConnection::ptr& conn, BaseMessage::ptr& msg) = 0;
    };

    template<typename T>
    class CallbackT : public Callback
    {
    public:
        using ptr = std::shared_ptr<CallbackT<T>>;
        using MessageCallback = std::function<void(const BaseConnection::ptr& conn, std::shared_ptr<T>& msg)>;
        CallbackT(const MessageCallback& handler):
            _handler(handler)
        {}

        void onMessage(const BaseConnection::ptr& conn, BaseMessage::ptr& msg) override
        {
            auto type_msg = std::dynamic_pointer_cast<T>(msg);
            _handler(conn, type_msg);
        }
    private:
        MessageCallback _handler;
    };

    class Dispatcher
    {
    public:
        using ptr = std::shared_ptr<Dispatcher>;
        template<typename T>
        void registerHandler(MType mtype, const typename CallbackT<T>::MessageCallback& handler)
        {
            std::unique_lock<std::mutex> lock(_mutex);
            auto cb = std::make_shared<CallbackT<T>>(handler);
            _handlers.insert(std::make_pair(mtype, cb));
        }

        void onMessage(const BaseConnection::ptr& conn, BaseMessage::ptr& msg)
        {
            //找到消息类型对应的业务函数再调用;
            std::unique_lock<std::mutex> lock(_mutex);
            auto it = _handlers.find(msg->mtype());
            if(it != _handlers.end())
            {
                return it->second->onMessage(conn, msg);
            }

            //没找到指定类型回调处理;
            ELOG("受到未知类型消息! ");
            conn->shutdown();
        }
    private:
        std::mutex _mutex;
        std::unordered_map<MType, Callback::ptr> _handlers;
    };
}